Twin plug jack



D. B. COON Get. 21, 1969 TWIN PLUG JACK Filed April 14, 1967 INVENTOR Donald B. Coon United States Patent US. Cl. 339-32 4 Claims ABSTRACT OF THE DISCLOSURE A twin jack structure having a pair of apertures each adapted to receive a different sized plug. The apertures are placed sufiiciently close together so that a second plug cannot be inserted into the open aperture when a plug is in the other aperture.

This invention relates generally to twin jack structures particularly of the type used in the communications field and more particularly to a twin jack structure having a configuration which will permit only a single plug to be inserted at any time.

In the communications field, it is desirable to provide twin jacks operable from either of two apertures. However, it is often a requirement that when either of the apertures is being utilized by a plug the other should be rendered inoperative.

It is therefore a principal object of this invention to provide a twin jack structure wherein the apertures are so located that if a plug is inserted in one aperture it will physically block the insertion of a plug into the other open aperture.

Another more particular object of this invention is to provide a twin jack structure having two different sized apertures each for receiving a different sized plug and wherein the apertures are so located that when a plug is inserted into one it physically prevents the insertion of a plug into the other.

These and other objects together with a fuller understanding of the invention will become more apparent from the following description taken in conjunction with the drawing in which:

FIGURE 1 is a side elevational view of a twin jack structure according to this invention;

FIGURE 2 is an exploded perspective view showing the elements of a twin jack structure according to this invention;

FIGURE 3 is a front elevational view of the apertured sleeve portion of the jack of this invention;

FIGURE 4 is a side elevational view of one size plug for one of said apertures; and

FIGURE 5 is a side elevational view of another size plug for the other aperture.

Referring now to the drawing, a twin jack structure according to this invention is shown in FIGURES 1 through 3. The jack structure is designed to be mounted in a front mounting panel represented by fragmentary section P in FIGURE 2.

The jack structure of this invention includes a mounting frame blanked out of sheet metal and having an upturned front portion 12. The upturned portion 12 is provided with a semi-circular opening 14 therein. The frame 10 also has a rearwardly extending flange portion 16 provided with a pair of threaded apertures 18 disposed to threadably receive a pair of screws 20 which support the stacked or pile up formation.

The stacked or pile up formation includes a tip spring 22 insulated from the frame member 10 by an insulating block 24, a ring spring 26 insulated from the tip spring 22 by an insulating block 28 and a contact member 30 3,474,382 Patented Oct. 21, 1969 insulated from the tip spring 26 by an insulating block 32. The tip and ring springs, the insulating blocks and the contact plates all have aligned apertures (unnumbered) through which the screws 20 pass and thread into the apertures 18 to secure the stack formation in place on the support frame 10. The tip spring 22 is formed with a pair of spaced contact extensions 34 and 36 of conventional design extending from a common crossover piece 37. Similarly, the ring spring 26 is formed with conventional design spaced contact extensions 38 and 40 extending from a common cross-over piece 41. Contact ears 42, 44, and 46 are Provided on springs 22 and 26 and contact plate 30 respectively to provide for the connection of wires.

A bushing or sleeve member 48 is provided which is shaped to slidably fit in the aperture 14 of the upstanding flange 12. The sleeve 48 is provided with a flattened upper portion 50 to mate with the shape of the aperture 14 and thereby prevent the sleeve from twisting in the aperture. The sleeve 48 is provided with a pair of through parallel aligned apertures 52 and 54. The aperture 52 is smaller than aperture 54 and each is of a size to receive one of a standard sized plug. The aperture 52 is slightly larger than the diameter D1 of the shank of the smaller plug shown in FIGURE 4 and the aperture 54 is slightly larger than the diameter D2 of the shank of the larger plug shown in FIGURE 5. conventionally, the diameters of the handle portions of the various sized plugs are the same and are shown as such as D3 in both FIGURES 4 and 5.

Referring now to FIGURE 3, it can be seen that the apertures 52 and 54 are located relatively close together. It is necessary that these apertures be located sufficiently close together so that if a plug of the type of either FIG- URES 4 or 5 is inserted in either of its respective apertures, it will be physically impossible to insert a plug in the other aperture. For this spacing, it is then necessary that the distance X (shown in FIGURE 3) between the centers of the apertures 52 and 54 be less than the diameter D3 of the handles of the plugs. In order to provide event a more positive block on the unused aperture, it is desired that the apertures 52 and 54 be suificiently closely spaced that a portion of the handle will actually physically cover a portion of the unused aperture therefore making even more difficult the insertion of anything into the unused aperture.

Turning again to the structure of the jack, the sleeve 48 must be provided with an annular insulating ring 56 and insulating spacer 64 if the panel P is made of a metallic or other conducting material. This insulating ring 56 is wrapped around the sleeve 48 where it is in contact with the panel to prevent short circuiting. The sleeve 56 is secured in the opening 14 and to the panel P by a nut 58 threaded thereon and a lock washer 60. The position of the front of the sleeve 48 can accurately be adjusted to give the proper spacing from the ends of the tip and ring springs by means of plastic spacers 62 which can he slipped over the sleeve 48 and be positioned between the front upturned portion 12 of support frame 10 and the rear of panel P. By the use of these plastic spacers, the front end of the sleeve 48 can always be accurately maintained with respect to the tip and ring springs irrespective of various thicknesses of the panel P by merely adding or removing spacers, as required.

Although one embodiment of this invention has been shown and described various adaptations and modifications may be made without departing from the scope of the appended claims.

What is claimed is:

1. A twin jack socket comprising, a frame member, a sleeve member secured to said frame member, said sleeve member having first and second plug receiving apertures formed therein, said apertures being sufficiently closely spaced that the distance between them is less than the combined radius of a pair of plugs to prevent the insertion of a second plug in one of the apertures when a first plug is inserted in the other of the apertures, and tip and ring spring means secured to said frame member and aligned with said apertures.

2. The twin jack socket of claim 1 wherein said first aperture is of a larger size than said second aperture.

3. The twin jack socket of claim 1 wherein said sleeve member is mounted in an opening of said frame member, and wherein spacer means are provided to selectively adjust the position of the front of the sleeve member with respect to the tip and ring springs.

4. The twin jack socket of claim 1 wherein said apertures are sufficiently closely spaced that the handle of a plug inserted in one aperture will overlie at least a portion of the unused aperture.

References Cited UNITED STATES PATENTS 2,746,023 5/1956 Tyzack 339176 2,997,687 8/1961 Walter 339291 3,108,843 10/1963 Frantz 339-183 X DAVID J. WILLIAMOWSKY, Primary Examiner P. C. KANNAN, Assistant Examiner US. Cl. X.R. 

